Data Sheet
JRW017-070 Series Power Modules DC-DC Converters
36-75Vdc Input; 1.2Vdc to 12Vdc Output
July 21, 2008
Test Configurations
Design Considerations
Input Source Impedance
The power module should be connected to a low
ac-impedance source. A highly inductive source
impedance can affect the stability of the power
module. For the test configuration in Figure 43, a
100μF electrolytic capacitor (ESR< 0.7Ω at 100kHz),
mounted close to the power module helps ensure the
stability of the unit. Consult the factory for further
application guidelines.
Output Capacitance
Note: Measure input reflected-ripple current with a simulated source
inductance (LTEST) of 12 µH. Capacitor CS offsets possible battery
impedance. Measure current as shown above.
High output current transient rate of change (high
di/dt) loads may require high values of output
capacitance to supply the instantaneous energy
requirement to the load. To minimize the output
voltage transient drop during this transient, low E.S.R.
(equivalent series resistance) capacitors may be
required, since a high E.S.R. will produce a
correspondingly higher voltage drop during the
current transient.
Figure 43. Input Reflected Ripple Current Test
Setup.
Output capacitance and load impedance interact with
the power module’s output voltage regulation control
system and may produce an ’unstable’ output
condition for the required values of capacitance and
E.S.R.. Minimum and maximum values of output
capacitance and of the capacitor’s associated E.S.R.
may be dictated, depending on the module’s control
system.
The process of determining the acceptable values of
capacitance and E.S.R. is complex and is load-
dependant. Lineage Power provides Web-based tools
to assist the power module end-user in appraising
and adjusting the effect of various load conditions and
output capacitances on specific power modules for
various load conditions.
Note: Use a 1.0 µF ceramic capacitor and a 10 µF aluminum or
tantalum capacitor. Scope measurement should be made using a
BNC socket. Position the load between 51 mm and 76 mm (2 in. and
3 in.) from the module.
Figure 44. Output Ripple and Noise Test Setup.
Safety Considerations
For safety-agency approval of the system in which the
power module is used, the power module must be
installed in compliance with the spacing and
separation requirements of the end-use safety agency
standard, i.e., UL* 60950-1 Recognized, CSA† C22.2
No. 60950-3-01 Certified, and EN 60950-1 (VDE‡
0805): 2001-12 Licensed.
Note: All measurements are taken at the module terminals. When socketing,
place Kelvin connections at module terminals to avoid measurement errors due
to socket contact resistance.
These converters have been evaluated to the spacing
requirements for Basic Insulation per the above safety
standards. For Basic Insulation models (“-B” Suffix),
1500 Vdc is applied from Vi to Vo to 100% of outgoing
production.
Figure 45. Output Voltage and Efficiency Test
Setup.
For end products connected to –48V dc, or –60Vdc
nominal DC MAINS (i.e. central office dc battery
plant), no further fault testing is required.
LINEAGE POWER
13
LINEAGEPOWER [ LINEAGE POWER CORPORATION ]
